A solar cell is a device that converts photons into electrical energy. The electrical energy produced by the cell is collected through electrical contacts coupled to the semiconductor material, and is routed through interconnections with other photovoltaic cells to form a photovoltaic module. The interconnections conventionally involve stringing cells together in series or parallel with ribbon bus bars, using two or three ribbons per cell. Automated methods for assembling photovoltaic modules have been developed to improve manufacturability and cost, such as using rollable sheets of solar cells, cell stringing machines and automated lamination. The cell strings are then connected to one or more junction boxes for the entire module using final ribbon runs. The final ribbon connections from the cells to the junction box are typically cut and soldered by hand.
A photovoltaic module also includes one or more bypass diodes to protect the module when cells within the module are not operating properly, such as due to damage or shading. A shaded cell reverse biases and consequently draws current from the module instead of producing current, which can result in electrical arcing and even fire, or hot spotting as referred to in the industry. In typical modules, one diode is required for a certain number of cells, such as approximately for every 18-24 solar cells. These diode connections add to the manufacturing steps that are required for assembling a photovoltaic module. Thus, numerous ribbon soldering steps and bypass diode connections are involved in fabricating a photovoltaic module, especially for large modules such as with sixty or more solar cells.